Phoenix, you gotta have the mast in the back half of the track at all times. I measured the 135cm point (from back of board) on my 80L evo and it's just behind the centre point of the mast track. Click here to read about the 135cm point and other neat tuning tips for wave boards.
http://www.boards.co.uk/articles/index.asp?ID_A=296&article_type=16 With my biggest sail and fin I'll put the mast in the very middle, but like Mark pointed out, any further forward and you're pushing water.
While I was getting used to the feel of the Evo I used stiffer fins (MFC FPT
www.mauifin.com/ ) 20.5cm for sails 4.2 - 5.2 and 22cm for 5.2 - 5.8 although a 23cm probably would have been a better choice. MFC 2K is also a good fin for Dutchies etc.
Recently I have gone back to the flexy Drake fin and am having a lot of fun with it - it is easy to spin out for some rad tail slides on smaller waves and it is also very nice for carving up decent waves.
I think the planing flat on the 2005 Evos is between the mast track and the front footstrap cos you have to drop your weight on the front foot briefly to release the tail, then shift back to keep the nose clear. Subtle movements but you'll get used to it in time. I also find that pumping the fin helps to get moving.
To point upwind you have to sort of "edge" like a kiter

. Although I leant the board to a mate a couple of weeks ago and he complained that it pointed too much! I guess it's just a technique thing.
The other thing is not to be put off by the short length - if you're used to a longer board, ride the Evo just like you would. If you're too conscious of the short length you will find you're weighting the back too much and bogging the board.
The best advice I got when I moved across to the Evo is that most people who get on them hate them at first, but once they get the hang of it they don't want to ride anything else. Keep persisting and you'll find the Evo to be a very rewarding board!